Puncture repair

I have just had one of my tyres punctured by a screw the tyre is fairly new approximately 6000 miles. The tyre people have plugged the hole €10 and said we are good to go and the plug “should” last the normal duration of the tyre.
I’m less convinced about their assessment should I just get a new tyre fitted or perhaps two to keep the axle the same?

I agree I've seen several plugs in tyres that are worn out with no thread left, when the came out first, it was suggested that you have a patch fitted over the plug on the inside later but I have only seen this done on racing slicks.
I keep a plug repair kit in the motorhome tool kit.